Hydraulic variable-speed transmission.



C. M. CONRADSON.

HYDRAULIC VARIABLE SPEED TRANSMISSION.

APPLICATION FILED AUG-7. 1913.

3 SHEETS-SHEET I.

Patented Mar. 28, 1916.

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c. M. CONRADSON,

HYDRAULIC VARIABLE SPEED TRANSMISSION.

APPLICATION man AUG-7. 191a.

Patented Mar. 28,

3 SHEETSSHEET 2.

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APPLICATION FILED AUG-7| 1913.

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CONRAD M. CONBADSON, OF MADISON, WISCONSIN.

HYDRAULIC VARIABLESPEED TRANSMISSION.

Specification of Letters Patent.

Application filed August 7, 1913. Serial No. 788,528.

To all whom it may concern:

Be it known that I, CONRAD M. CONRAD- SON, citizen of the United States, resident of transmission capable of application to a variety of uses, but designed particularly for operating the reciprocating bed or carriage of a planer, shaper, or similar machine.

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claims.

In the accompanying drawings forming part of this. specification, Figure 1 is a vertical sectional view of a hydraulic pump apparatus embodying my invention, Fig. 2 is a similar view taken on section line m-w of Fig. 1, looking in the direction of the arrow, showing the plunger shaft of the'cylinders in its central position, Fig. 3 is a similar view looking in the opposite direction and showing the shaft in its eccentric position, Fig. 4 is a sectional View, on the line y-y of Fig. 1, Fig. 5. illustrates the application of the hydraulic transmission to a reciprocating bed or carriage.

In the drawing, 2 represents the base of the pump, having a casing 3 mounted thereon provided with heads 4 and 5. The head 4 has a bearing 6 for a driven shaft 7 that is provided with a pulley 8, driven through a belt 9 (see Fig. 5) from a suitable source of power (not shown). A pinion 10 is provided at the inner end of the shaft 7 and a ring 11 encircles this pinion and is provided with an internal gear to mesh, with the teeth of said pinion. The head 4 has a hub 12 centrally arranged thereonand the head 5 is provided with ahub 13. A sleeve 14 encircles the hub 12 and is free to turn thereon at one end and is provided at its opposite end with a tapered inner surface 15 which engages a similar surface 16 formed on the hub 13 and making an oil tight joint therewith. A ring 16' is preferably provided having adjusting screws 16" and adapted to bear on theend of the sleeve 14 for the purpose of taking up-wear in the sleeve and its bearings. The sleeve 14 is provided with a series of cylinders 17 having heads 18, andv Patented Mar. 28, 1916. a

between these cylinders, which are arranged .at suitable intervals around the periphery of the sleeve, are webs 19 secured to the ring 11 by suitable means, such as bolts 20. A shaft 21 is mounted to slide in horizontal slots 22 provided in'the hubs 12 and 13, said shaft being capable of adjustment from one side ofthe center .of the heads 4 and 5 to the other side of the center thereof. and is therefore eccentric with respect to the axis of the heads 4 and 5 and their hubs. There may be any'suitable number of the cylinders 17, but I have shown five of them in this case, from the use of which the desired results can be obtained. I do not, however, limit myself to this number.

Each cylinder is provided with a piston 21 having a connecting rod 22' provided with a T-head 23 that is adapted to bear on the cylindrical portion 24 of the shaft 21 at a point midway, substantially, between the ends of said shaft and between the hubs 12 and 13, a space 25being provided between the cylinders and said shaft to accommodate the connecting rods 22 and permit freedom of revolution. The T-heads 23 bear on the shaft and are held in place thereon by means of rings 26 having recesses 27 to receive the heads 23 of the connecting rods. The connecting rods are-thus held at all times in contact with the surface 24 to be actuated with one chamber and the other three with the other chamber. I This form of communication will, of course, be reversed continuously as the machine operates. The chamber 28 has a port 31 leading from the chamber 28 to a pipe 32 and a similar port leading'from the chamber 29 to a pipe 33. These cylinder 34 having a piston 35 and rods 36 on each side thereof which slide in bearings in the end walls of the cylinder. By having the piston rods on each side of the piston I am able to provide chambers on opposite sides of the piston of equal capacity.

This arrangement allows an equal volume of inelastic fluid to flow into both chambers and avoids the necessity of a relief or reservoir chamber in connection with the cylinder. The cylinder is provided with suitable vent cocks 37. Pipes 38 and 39 lead from the pipes 32 and 33' to a pan 40. The

chambers and cylinders within the pump, the cylinder 34 and the pipes 32 and 33 form a circulating system wherein a quantity of inelastic fluid suchas oil,- is placed.

To offset the leakage incidental to the operation of a machine of this type a pan 40 is preferably provided, supplied with oil, which is drawn into the system through the check valves 41 on the suction stroke of the pistons as they are successively connected with the pipes 38 and 39.

When the system is filled with oil and the shaft is shifted to an eccentric position, one group of the pistons will be-moved outwardly to a point near the heads of their cylinders, while the pistons of the other group will be drawn inwardly away from the heads of their cylinders and consequently the oil forced out of the cylinders by the first group of pistons and into one end of the cylinder 34 will drive the piston 35 toward the other end of the cylinder 34 and force the oil in said other end through the pipe to the cylinders of the second group of pistons. The piston rod 36 is provided with an arm 42 attached to a reciprocating bed or carriage 43. An arm 44 is mounted on this carriage and adapted to slide over a rod 45 supported in guides 46 and provided withadjustable collars 47. A bell crank 48 has one arm loosely connected at 49 with the rod 45 and the other .arm of the bell crank is'connected bya rod 50 with an arm 51 mounted on a shaft 52 that is provided with an arm 53. A screw 54 is mounted in the arm53 and a rod 55 is pivo-tally connected with a collar 56 which has a threaded connection with the screw 54 and is capable of adjustment up and down thereon. The adjustment of the collar 56 on the screw 54 toward or from the shaft 52 obviously will regulate the longitudinal movement of the rods 55 and 58 and the stroke of the shaft The rod 55 is connected by a turn buckle 57 with a rod 58 having a forked end 59 that is mounted on the projecting ends of the shaft 21 to move said shaft to an eccentrlc or concentric position when said rod 58 is actuated by the rocking of the bell 35 in the stationary cylinder and the stroke In other of the revolving cylinder pistons. words, the nearer the shaft 21 is adjusted to its central or concentric position with respect to the revolving cylinders, the slower the movement of the piston 35, and the farther the shaft is moved fromits center, the greater will be the speed of the piston 35. The length of the stroke of the piston 35 and of the reciprocating bed towhich it is attachedis varied by means of the adjust: ment of the collars 47 on the rod. 45. Obviously, the nearer these collars are adjusted to one another, th shorter will be the stroke of the piston, and the farther they are moved apart the longer the stroke of the piston. At the end of each stroke, the sliding shaft forming the axis of the revolving cylinder piston rods will be shifted and the movement of the piston 35 reversed and this will continue automatically as long as the pump cylinders and pistons are revolved. I am thus able, by applying a constant speed to the pump, to convert a rotary to a con: tinuous reciprocating movement and at a variable speed.

I may operate the rod 55 through a lever 60 instead of operating it through the rod. 45 and the'collars 47, and I alsovprefer to provide a weight 61 in the arm 53 to insure the positive movement of the shifting mechanism past the cent-er in each direction.

I do not wish to be confined to the means shown for'connectingthe pump with the reciprocating. bed, as in various ways this mechanism may be modified and still be within'thescope of my invention.

I claim as my invention:

1. A hydraulic variable speed transmission comprising a casing, a plurality of cylinders mounted to revolve therein, a shaft having bearings at its ends in said casing, connecting rods having bearings on said shaft intermediate to the ends thereof I and pistons in said cylinders, said shaft bea ing normally concentric with the axis of said cylinders but capable of lateral adjustment in guides in said casing to an eccentric position to increase or decrease the stroke'of said pistons, a stationary cylinder having "a piston and ports on each side thereof communicating with said revolving cylinders and forming-therewith a circulats fluid, and means for moving said shaft to reverse the stroke of said revolving cylinder pistons.

2. In a hydraulic variable speed transmission, a casing, heads therefor having inwardly projecting hubs provided with radial slots therein, a shaft mounted to slide.

and communicating therethrough with said cylinders, and means for shifting said shaft to an eccentric position with respect to the axis of said cylinders to vary the stroke of said pistons.

3. The combination, with a stationary casing having oppos1ng,inw ardly projecting hubs provided with radial slots therein, a shaft mounted to slide laterally in said slots, a sleeve mounted to revolve on said hubs, a plurality of radially arranged cylinders mounted on said sleeve to revolve therewith, pistons for said cylinders, connecting rods. for said pistons having bearings on said shaft,- said casing having chambers thereinand ducts leading from said chambers to said cylinders, said cylinders being divided into two groups and said chambers communicating alternately with said groups as said cylinders revolve, means for shifting said shaft laterally with respect to the axis of said cylinders to vary the stroke of said pistons, and means reciprocated continuously by the movement of said pistons and at a variable speed by the shifting of said shaft.

4."- A hydraulic pump comprising a casing and heads therefor, said heads having opposing hubs thereon, one of said hubs having a tapered bearing face, a sleeve, journaled on said hubs and provided with a beveled face to engage the corresponding face of said hub, means for setting the tapered face of said sleeve against the corresponding face of said hub, a plurality of cylinders mounted on said sleeve, pistons therefor, a shaft having a radial movement in said hubs and whereon the rods of said pistons are journaled. means for revolving said sleeve and cylinders, and inelastic fluid supply pipes communicating with said cylinders.

5. The combination, with a casing having fluid supply and return ports, of a member mounted to revolve within said casing provided with a plurality of cylinders and ducts leading from said cylinders to said ports, said member having a tapered hearing on the walls of said ports and forming a fluid tight joint therewith, pistons for said pistons.

cylinders, 'and connecting rods therefor, an

axis whereon said connecting rods are mounted, said axis having a movement in said revolving member transversely with respect to the center thereof, to vary the stroke of said pistons.

6. A rotary pump comprising a casing having a head provided with intake and return ports therein, a revolving member provided with a plurality of cylinders and ducts therein arranged to communicate alternately with said ports and having a bearing adjacent to said ports, means in theopposite head of said casing for seating said revolvmg member in said bearing to take up wear, pistons for said cylinders and connecting rods therefor, the axis of said connecting rods havingbearings at each end in said casing and belng adjustable transversely of said member and said head for varying the stroke of said pistons.

7. A device of the class described com-' prising a casing having headsand slots therein, a revolving member journaled between said heads and having a plurality of cylinders and fluid ducts leading therefrom, one of said heads having ports com municating alternately with said ducts assaid member revolves, an axis mounted to move in said slots from one side to the-other of said revolving member and pistons for said cylinders having connecting rods mounted on said axis and means for shifting said .axis to vary the stroke of said 8,. A hydraulic variable speed transmission comprising a rotary pump including fluid supply and return pipes, a revolving member having a plurality of cylinders and ducts therefor arranged to communicate alternately with said supply and return pipes, pistons for said cylinders, an axis movable transversely of said pump and having a bearing for said pistons, and means for shifting said axis to vary the stroke of said pistons and a reciprocating member communicating with said pipe connections and arranged to actuate said shifting means to reverse the stroke of said pistons.

9. A hydraulic variable speed transmission comprising a casing having a head provided with chambers therein and supply and return pipes therefor, a member mounted to revolve within said casing and having a plurality of cylinders and ports leading to said cylinders arranged to alternately communicate with said chambers, a shaft having bearings in said casing and movable transversely thereof across the center of the axis of said cylinders, pistons for said cylinders having connecting rods mountedv on said shaft, the adjustment of said shaft varying the stroke of said pistons, a cylinder communicating with said supply and return der and means actuated through the move ment of said reciprocating piston for shifting the position of said shaft to reverse the stroke of said revolving pistons.

10. A rotarypump comprising a casing and heads therefor, one of said heads having supply and return ports, a member mounted to revolve between said heads and having bearings thereon, said member having a gear ring thereon within said casing, a driving shaft having a pinion meshing-with said gear ring, said member having a plurality of radially arrangedcylinders therein and ducts therefor arranged to communicate alternately with said ports, pistons for said cylinders and connecting rods therefor, the

' axis of said connecting rods being adjustable transversely of said heads for varying the stroke of said pistons.

11. A rotary pump comprising a casing provided with a head having supply and return ports, a member mounted to revolve within said casing and having a plurality of cylinders provided with ducts arranged to communicate alternately with said ports, a shaft having bearings at its ends in said casing -and movable transversely thereof, pistons for said'cylinders, and connecting rods therefor, said connecting rods having end portions adapted to bear on the middle portion .of said shaft and means encircling said shaft and engaging said end portions for holding them thereon while allowing freedom of oscillation of said connecting rods to accommodate themselves to the varying positions of said pistons, and means for shifting said shaft to vary the stroke of said pistons.

12. A rotary pump comprising a casing having a head provided With supply and return ports, a member mounted to revolve within said casing and having a plurality of cylinders and ducts therefor arranged to communicate alternately with said ports,

a shaft having bearings at its ends in said casing and mounted to move transversely thereof across the axis of said revolving member, pistons'for said cylinders and con necting rods therefor, having T-shaped heads seated on the middle portion of said shaft and rings encircling said shaft and engaging said T-shaped heads and means arr-mesa for shifting said shaft to vary the stroke of said pistons, 13. A hydraulic variable speed transmlssion comprising a rotary pump operated at: a constant speed and lncludmg revolving cylinders and pistons and connecting, rods having a common axls, a' reciprocatlng mem her having pipe connections with said cylinders for fluid pressure circulation, means actuated by the movement of said member in both directions and having a forked connection with the ends of the axis of said 1 connecting rods to shift it laterally and l reverse the stroke of sald pistons, said actuated means having a part for increasing the momentum of said means and insuring the completion of its stroke when actuated by said reciprocating member. 7

14. A hydraulic variable speed transmishaving pipe connections with said cylinders for fluid pressure circulation, a rockshaft, a lever mounted on said shaft and connected- With the axis of said connecting rods andactuated by the movement of said member in both directions for shifting the axis of said rods to reverse the stroke of said piston,

and a Weight adjustably mounted on said.

lever, for the purpose specified.

15. A hydraulic variable speed transmis sion comprlsing a pump having, cylinders and pistons and connecting rods therefor, a

reciprocating member having pipe connections. with said cylinders for fluid pressure circulation, a rock shaft, a rod connected to said piston rods and to said shaft and ad-.

justable toward and from the axis of said shaft, for varying the stroke of said piston rods, and means connected with said shaft and disposed in the path of said reciprocate ing member to be actuated thereby to reverse the member.

In witness whereof, I have hereunto set my hand this 31st day of July, 1913.

CONRAD M. CONRADSON.

Witnesses FRED. ARNOLD, F; MoDonoocnaJ r. 

